CVE-2026-53639: Sylius: IDOR on Shop Payment Request API endpoints

The GET /api/v2/shop/payment-requests/{hash} and PUT /api/v2/shop/payment-requests/{hash} endpoints look up the payment request solely by the hash from the URL. No ownership check is performed against the authenticated customer or the underlying order.

An attacker who obtains a payment request hash can:

• read the payment request and, through the payment IRI in the response, recover the underlying order’s tokenValue (which itself grants access to the full order, items, addresses, customer email, totals);
• update the payment request payload (e.g. target_path, after_path). These fields are used by the front-end controller to redirect the user after the payment, so an attacker can flip them to an attacker-controlled URL and intercept the buyer.

The hash is a UUID, so it has to be obtained out-of-band (logs, shared links, referrer headers, a co-located client), but once it is known no other credential is required, neither authentication nor knowledge of the order token.

The creation endpoint POST /api/v2/shop/orders/{tokenValue}/payment-requests shares the same flaw: it resolves the target order solely from the tokenValue in the URL without verifying that the caller owns the order.